U.S. Pat. No. 4,490,351 describes the utilization of liquid perfluorocarbons for treatment and diagnosis in ophthalmology. While such substances are used for temporary treatment of retinal detachments and as vitreous body tamponade, their long-term use, for example as vitreous body substitute, is connected with various kinds of injury to the eye. There are known side effects, for example, from perfluoropolyethers and perfluorocarbons, which are due to mechanical injuries at the retina and visual nerve, where the high density (about 1.9 g/cm3) of these compounds is blamed for this.
On the other hand, partially fluorinated liquids that only have a density between 1.1 and 1.3 g/cm3 and which can be used as auxiliary agents in ophthalmology for retinal unfolding, for vitreous body tamponade and as a vitreous body substitute have been proposed in the publications EP 0 563 446 A1, DE 195 36 504 A1 and DE 197 19 280 A1. These substances, too, in spite of their clearly lower densities, lead to histological changes in the region of the retina and even to the side effects that are otherwise known for perfluorinated carbons.
Finally, DE 44 05 627 A1 and EP 05 45 174 A1 describe fluorocarbon-containing oligomers of the general formula (RF)x—RH where RF means a highly fluorinated alkyl residue, which is bonded directly or via a bonding link to the RH group, which stands for an alkane residue or hydrogen and x means a number from 1 to 4, and which are prepared from compounds of the general formula Y—(CF2)a-Ob—(CH2)c—CH═CH2, where Y stands for a hydrogen or fluorine atom, a is a number from 2 to 16, and b and c are independently a number between 0 and 1, and d is a number between 0 and 6, with an average degree of oligomerization from 2 to 4. In said publications the described substances are described as being used as greases or lubricants and as ski base materials and also as oxygen carriers.